Alpha-1 Antitrypsin Genotype Distribution in Patients with Emphysema

Area of Science:

• Pulmonology
• Genetics
• Rare Diseases

Background:

• Alpha-1 antitrypsin deficiency (AATD) is an inherited condition causing low alpha-1 antitrypsin (AAT) levels.
• AATD is a known risk factor for emphysema, a serious lung condition.

Purpose of the Study:

• To determine the frequency of AATD in emphysema patients.
• To analyze AATD genotype distribution based on emphysema type and location.
• To evaluate AATD patients for augmentation therapy eligibility.

Main Methods:

• A cross-sectional study of 794 emphysema patients using high-resolution computed tomography (HRCT).
• Collected demographic data, smoking status, emphysema type/location, and performed AAT genotyping via dried blood spots.
• Assessed AAT levels and pulmonary function tests (PFT) in diagnosed AATD patients.

Main Results:

• AATD mutations were found in 4% (31/794) of patients; 96% had no mutations.
• AATD was more prevalent in panacinar emphysema.
• Common mutations included PI*M/M malton, PI*M/Z, PI*M/I, and PI*M malton/M malton. Low AAT levels were observed in PI*Z/Z, PI*M malton/M malton, and PI*Z/M malton genotypes. Six patients received augmentation therapy.

Conclusions:

• Analyzing AAT genotypes in emphysema patients facilitates early AATD diagnosis.
• Early diagnosis enables prompt implementation of preventive strategies and augmentation therapy.
• Genotyping contributes to personalized management of emphysema in AATD patients.